【正文】 編 號(hào)本 科 生 畢 業(yè) 設(shè) 計(jì) （ 論 文 ）題目： 聚乳酸復(fù)合材料結(jié)晶性能的研究 化學(xué)與材料工程 學(xué) 院 高分子材料與工程專 業(yè)學(xué) 號(hào) 學(xué)生姓名 指導(dǎo)教師 摘 要本文采用成核劑VP101t 、共混型立構(gòu)復(fù)合聚乳酸 (SCPLA)和嵌段立構(gòu)復(fù)合聚乳酸PDLAPLLAPDLA(DLDPLA)作為成核劑，制備聚乳酸/VP101t、聚乳酸/SCPLA和聚乳酸/DLDPLA 復(fù)合材料，考察了不同成核劑對(duì)復(fù)合材料結(jié)晶性能的影響．利用DSC 和XRD對(duì)復(fù)合材料的結(jié)構(gòu)和結(jié)晶性能進(jìn)行研究．結(jié)果表明：三種物質(zhì)都可提高PLA的結(jié)晶速率和結(jié)晶度；XRD結(jié)果表明，三種物質(zhì)的加入沒有改變PLA的晶型．通過溶液揮發(fā)法制備了不同配比的PLA/CNT復(fù)合材料．采用掃描電子顯微鏡(SEM) 研究了CNT在PLA中的微觀形態(tài)，發(fā)現(xiàn)CNT在PLA基體中分散性較好，分別通過差示掃描量熱儀(DSC) 、X 射線衍射(XRD)和萬能試驗(yàn)機(jī)來研究 CNT的加入對(duì)PLA的結(jié)晶、結(jié)晶結(jié)構(gòu)及力學(xué)性能的影響．結(jié)果發(fā)現(xiàn)，CNT的加入提高了PLA的結(jié)晶速率、結(jié)晶度和力學(xué)性能．CNT在基體中的分散直接影響了PLA的性能，為了使 CNT更好的分散在PLA 基體中，通過溶液沉淀法制備了不同含量CNT的納米復(fù)合材料．SEM及XRD的結(jié)果均表明，與溶液揮發(fā)法比較，溶液沉淀法可有效的抑制了CNT的團(tuán)聚，達(dá)到較好地分散，并對(duì)其晶體結(jié)構(gòu)、結(jié)晶性能及力學(xué)性能進(jìn)行研究．結(jié)果發(fā)現(xiàn)，CNT的加入不但提高了PLA的結(jié)晶度，并且改變了結(jié)晶結(jié)構(gòu)，促進(jìn)PLA向α晶型轉(zhuǎn)變．隨著CNT含量的增加，PLA結(jié)晶度減小，但其熱穩(wěn)定性和力學(xué)性能卻有較大的提高．關(guān)鍵詞：聚乳酸；納米復(fù)合；結(jié)晶；成核劑；碳納米管ABSTRACTIn this paper, polylactic acid (PLA) was modified by solution casting method using nucleating agents VP101t, stereoplex (SC) PLA and triblock stereoplex copolymer (DLDPLA). The crystallization of the posites were studied by using Xray diffraction(XRD) and differential scanning calorimetry(DSC). It was shown that the crystallinity of the posites was improved, although crystal forms did not change.PLA/CNT nanoposites with varied CNT percent were prepared via solution casting method for the first time in this work. The micromorphology of PLA nanoposites was characterized by scanning electron microscopy(SEM). The influence of CNT on the crystal structure, crystallinity and mechanical properties of PLA was investigated by Xray diffraction(XRD), differential scanning calorimetry(DSC) and tensile test, respectively. SEM observation indicated that CNT were dispersed in the PLA matrix very well. It was found that the presence of CNT had enhanced significantly the crystallinity and mechanical properties, but did not change the crystalline structure.The micromorphology of CNT in the PLA matrix had strong effect on the properties of PLA. Solution coagulation method was used to prepare the PLA/CNT nanoposites with various CNT loadings percent so as to get the better dispersion. This method indeed refrained the agglomeration of CNT effectively pared to the solution casting method which was confirmed by SEM and XRD results. SEM observation indicated that CNT was nicely good dispersed in the PLA matrix. The results indicated that the crystal form changed and overall crystallinity of PLA/CNT nanoposites decreased with increasing the CNT loading. The thermal stability and mechanical properties had been apparently improved in the PLA/CNT nanoposites with respect to these prepared via solution casting method.Keywords: Polylactic acid。 posite。 crystallization。 nucleating agents。 carbon nanotube目 錄第 1 章 緒論 .............................................................................................................1 概述 .......................................................................................................................................1 聚乳酸的合成 .......................................................................................................................1 直接縮聚 ..............................................................................................................................................1 開環(huán)聚合 ..............................................................................................................................................2 聚乳酸的分子結(jié)構(gòu)和晶體結(jié)構(gòu) ...........................................................................................2 聚乳酸結(jié)晶的研究 ...............................................................................................................5 共混 ......................................................................................................................................................6 共聚 ......................................................................................................................................................6 結(jié)晶成核劑 ..........................................................................................................................................7 成型條件 ..............................................................................................................................................7 聚乳酸的應(yīng)用領(lǐng)域 ...............................................................................................................8 生物醫(yī)學(xué)用途 ......................................................................................................................................8 農(nóng)業(yè)用途 ..............................................................................................................................................9 包裝用途 ..............................................................................................................................................9 紡織用途 ..............................................................................................................................................9 聚乳酸材料的前景 .............................................................................................................10 選題意義和研究?jī)?nèi)容 .........................................................................................................10 選題背景 ............................................................................................................................................10 選題目的和意義 ................................................................................................................................12 研究?jī)?nèi)容和創(chuàng)新點(diǎn) .............................................................................................................12 研究?jī)?nèi)容 ............................................................................................................................................12 研究方案 ...................................................................